Remark Code MA13 on Your EOB — Meaning & What to Do

Remittance Advice Remark Code (RARC)

What remark code MA13 means: You may be responsible for a portion under a specific program rule.
What to do about remark code MA13: Confirm this cost-share with your insurer.

Remark codes add detail to a claim decision. They appear alongside the main adjustment codes on your Explanation of Benefits or remittance notice, giving the specific reason behind remark code MA13.

Seeing remark code MA13 on your EOB?
A denial code tells you what the payer reported, but it may not tell the whole story. Reviewing your EOB and bill together can help clarify what may need attention.

Check My EOB

Related codes

Keep reviewing your bill

Frequently asked questions about Remark code MA13

What does remark code MA13 mean on my EOB?

You may be responsible for a portion under a specific program rule.

What should I do about remark code MA13?

Confirm this cost-share with your insurer.

Seeing this code on your own EOB?
Upload the EOB, the bill, or both — MD Bill Check reads the codes on your documents, compares them side by side, and flags what's worth questioning. Free, no account needed.

Check My Bill & EOB

Last reviewed 2026-07-07 · MDBillCheck Editorial Team. Plain-English explanations are original wording; always verify the specific reason with your insurer.